2019-04-01 CAR UK (1)

(Darren Dugan) #1
APRIL 2019 | CARMAGAZINE.CO.UK 27

I


t might be fully electric, but just one run through a coned
course reveals this zero-emissions prototype Mini retains
all the fun of a Cooper S. Perky acceleration, direct steering,
fleet-footed agility – it all survives the transition from petrol to
plugs. Even the price is likely to be similar when the first cars
leave Oxford late this year, at £29k before a government grant.
Called the Mini Cooper S-E, it marks BMW’s first shot at a
series-production Mini EV over a decade after the 600-unit,
lease-only Mini E. That test-bed’s EV hardware was so bulky
it consumed the rear seat and demolished boot space, but it
informed the BMW i3. Appropriate, then, that the i3’s electric
drivetrain has been engineered into the Cooper S-E.
Beneath the floor, a lithium-ion battery is mounted in a

Mini electrifies


the hot hatch


Can Mini make its first electric car, the Cooper S-E, fun
to drive? We drive an early prototype. By Ben Barry

T-shape. It shares the i3’s battery chemistry, but the T makes it
smaller than the square i3 battery, and it’s rated at 92Ah, not the
94Ah of the 2017 i3. New i3s have since improved to 120Ah.
The power electronics normally found at the rear of the
i3 S – the hotter i3 – are packaged under the Mini’s bonnet, with
a single 181bhp e-motor driving the front wheels.
The 1350kg kerbweight represents a palatable 120kg penalty
over a Cooper S auto, and changes to the body-in-white are
minimal, so there’s no compromise to interior or boot space.
Flick a switch in the Mini’s familiar central row of toggles
and the Cooper S-E wakes with a synthesised greeting. There
are three drive modes; only Mid setting is accessible today.
Claimed acceleration is in the 7-8sec 0-62mph ballpark and
that’s how it feels – energetic enough if never truly rapid from a
standing start. The wow factor comes with powering through
a tight corner – torque not only feels instant and generous but
the S-E puts it down staggeringly well, exhibiting little of the
scrabble of punchy petrol Minis. The Mini EV then carries that
enthusiasm into silent mid-range thrust.
The Cooper S-E feels four-square squat through slaloms,
with a grippy front end, swift steering and limited roll. There’s
just as much weight over the nose as a petrol Cooper S, but the
centre of gravity is lower and the battery shifts the weight bal-
ance significantly rearwards, from a petrol ’s 60:40 front-to-rear
to 54:46. Throw in that short wheelbase and you get a highly
throttle-adjustable machine that dances through cones like a
shopping trolley dodging pensioners –though stability control
damps the fun and can’t be entirely disengaged.
There are two flavours of regenerative braking. The first is
as fierce as we’ve become accustomed to with EVs – lifting the
throttle often suffices for braking. The second is more compa-
rable to a petrol model, with a natural coast off-power.
The biggest negative relates to the steering during aggressive
driving. It feels lumpy and inconsistent, tugged by torque
flowing to the front tyres. Balancing the S-E’s rollercoaster
on-power cornering thrills with more consistent steering will
be a challenge for the remainder of the development process.
Overwhelmingly, though, the Cooper S-E entertains as the
label says it should. The biggest question regards how easy it’ll
be to own. We know an 80 per cent charge will take 40 minutes
on relatively uncommon 50kW DC chargers, three hours on
more numerous 11.2kW AC chargers, or 12 hours to charge fully
on a three-pin socket at home.
The range requires more guesswork. The 94Ah i3 is most
comparable; that offered a range of 146-158 miles on the WLTP
test, yet it was a more aerodynamic car some 105kg lighter. The
Mini’s range will almost certainly fall below that. The killer
question is by how much.

COOPER S-E: THE DETAIL


EASY PRODUCTION
The Cooper S-E will roll down the same
production line as other Minis at Plant
Oxford. Minimal changes to the body-
in-white help – a frame bolts power
electronics to existing three engine-
mount points, and charge sockets are
hidden behind the familiar fuel filler.


i3 S POWER
Electric motor is rated at 181bhp, as
is the BMW i3 S. It’s juiced by a 92Ah
lithium-ion battery, most comparable to
the 2017 i3’s 94Ah – though the latest
i3’s rated 120Ah. Gearing is taller than
the i3, due to Mini’s smaller wheels.
Expect 7-8sec 0-62mph and 90mph.


TIGHT PACKAGE
Battery is arranged in a T-shape with
the top of the T across the rear axle.
Interior and boot space is unaffected,
though there’s slightly less foam in


rear seats so rear-passengers’ hip
points are unchanged. Electric motor
is packaged between front wheels,
power electronics on top, and turned
90º versus the i3.

CHARGING AND RANGE
An 80 per cent charge takes 40
minutes on 50kW DC rapid charger,
three hours on 11.2kW AC chargers
and 12 hours on a three-pin domestic
socket. Expect range below 150 miles.

WEIGHT DISTRIBUTION
Versus petrol Cooper S, weight
distribution shifts rearwards due to
the battery. Ride height raised ‘1-2cm’
to give battery more clearance, and
weight increases 120kg over Cooper S
auto, but centre of gravity is lower.

CHASSIS TUNE
Suspension settings very different,
tuned to feel comparable to Cooper S.
Only 16- or 17-inch alloys available –
the ride is too firm on 18s.

i3S power electronics sit (very) snugly
under the bonnet in the Mini


Weight is
concentrated lower
down and further
back than Cooper S
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